The present invention relates to X-ray tubes and more particularly to a method and construction of an X-ray tube for producing X-rays over a specified range of emission angles with enhanced power output and high duty cycle.
The maximum X-ray power output from an X-ray tube is an important parameter in the operation and maintenance of a radiological system. The time period required to inspect an object is inversely proportional to the X-ray power output. In addition, for a given X-ray power output of the X-ray tube, tube lifetime increases substantially as its maximum power rating increases. Accordingly, the effect of using X-ray tubes with higher values for the maximum X-ray power output than presently available, is to reduce the inspection times and increase the throughput of patients or objects examined with the radiological system, as well as to reduce the maintenance and operating costs because of the longer tube lifetimes.
In X-ray tubes in current use, a beam of high energy electrons is directed at about 80.degree. to 90.degree. at an X-ray producing target with an incident angle with respect to the target surface in the region between 70.degree. and 90.degree. (most commonly at 80.degree.).